Radar and antenna built in radar

1. A radar, comprising: a transmitter antenna unit that includes multiple transmitter antennas; a receiver antenna unit that includes a first receiver antenna group including multiple first receiver antennas arranged at a first horizontal interval and multiple second receiver antennas arranged at the first horizontal interval and a second receiver antenna group including multiple third receiver antennas arranged at one or more second horizontal intervals, the first horizontal interval being smaller than each of the one or more second horizontal intervals; a transceiver that transmits sending signals through the transmitter antenna unit and receives returning signals reflected from a target object trough the receiver antenna unit; and a processing unit that derives information about the target object by processing the received returning signals.

2. The radar of claim 1 , wherein the multiple transmitter antennas are arranged at a vertical interval, of which size is equal to a size of the first horizontal interval.

3. The radar of claim 2 , further comprising: a virtual receiver antenna forming unit that forms one or more virtual receiver antenna groups arranged in a same horizontal direction as the first receiver antenna group and the second receiver antenna group and having a vertical offset of the vertical interval when multiple-input multiple-output processing is performed through the multiple transmitter antennas arranged at the vertical interval.

4. The radar of claim 3 , wherein at least one of the multiple third receiver antennas comprises at least three array antennas.

5. The radar of claim 4 , wherein if the first horizontal interval is K, the second horizontal intervals include at least 4 K and 7 K.

6. The radar of claim 5 , wherein the multiple third receiver antennas are arranged at the second horizontal intervals between the multiple first receiver antennas and the multiple second receiver antennas.

7. The radar of claim 6 , further comprising: an interpolation unit that forms antenna patterns arranged at the first horizontal interval within a horizontal area corresponding to the multiple first receiver antennas, the multiple second receiver antennas, and the multiple third receiver antennas by applying non-uniform linear array (NLA) interpolation to the multiple first receiver antennas, the multiple second receiver antennas, and the multiple third receiver antennas.

8. The radar of claim 7 , wherein the virtual receiver antenna forming unit forms one or more virtual receiver antenna groups having a vertical offset of the vertical interval in the antenna patterns arranged at the first horizontal interval.

9. The radar of claim 1 , where each of the multiple first receiver antennas and multiple second receiver antennas is a single array antenna, and at least one of the multiple third receiver antennas comprises at least three array antennas.

10. An antenna built in a radar, comprising: a transmitter antenna unit that includes multiple transmitter antennas; and a receiver antenna unit that includes a first receiver antenna group including multiple first receiver antennas at a first horizontal interval and multiple second receiver antennas arranged at the first horizontal interval and a second receiver antenna group including multiple third receiver antennas arranged at one or more second horizontal intervals, the first horizontal interval being smaller than each of the one or more second horizontal intervals.

11. The antenna of claim 10 , where each of the multiple first receiver antennas and multiple second receiver antennas is a single array antenna, and at least one of the multiple third receiver antennas comprises at least three array antennas.

12. The antenna of claim 10 , wherein the multiple third receiver antennas are arranged at the second horizontal intervals between the multiple first receiver antennas and the multiple second receiver antennas.